There is, IIRC, actually a ruling that says that offside should be judged at the moment when the player making the pass actually makes contact with the ball for his pass, not when the ball is released.
So why is it that on the NBC freeze frame, like the one sky used after Raheem scored, at the point he plays the ball Kevin's right leg is more or less upright, but on the freeze frame used by VAR his leg is extended and the ball is, as many have said, elongated due to the freeze frame. In other words, it's not when his foot makes contact with the ball, it's as it leaves it.
So why did VAR use the wrong frame? To my mind that can only be deliberate.